Boiler-scale-removing device



June 3, 1930. B. SPRATT 1,761,371

BOILER SCALE REMOVING DEVICE Filed July 3, 1928 y 2 Sheets-Sheet 1 Inventor Attornqy June 3, 1930.' s A T BOILER SCALE REMOVING DEVICE Filed July 3,! 1928.

2 Sheets-Sheerl 2 ln v emfor' 23/ 0? $787? Patented 1 June 3, 1930 BAYLOR SPRATT/OF Ev i svILLninnIANA BOILER-SOALE-R-EMOVING DEVICE Application filed July ,3, 1928. Serial No. 290,219.

The present inventionrelates to improvements in scale removers for boilers.

It is a well known fact that the scale and sediment will collect on the bottom'of a boiler, which portion 'of the boiler is exposed to the fire and tremendous heat, The scale and sediment collect in small piles and keeps the water from coming in contact with the bottom of the shell or" the boiler and consequently the plates become overheated and the pressure in the boiler causes the boiler plates to bag or burn. It is therefore one of the important objects of the present invention to provide a means that will remove the scale and sediment from the bottom of the shell of the boiler and discharge the same into the usual mud drums or settling Chambers located below and in communication with the boiler. A further object is to provide a boiler scale removing device that can be readily and easily installed without necessitating any material alteration, said device including a travelling scraper member and is oper-. able within the boiler from the outside.

A further scale removing device wherein means is provided for preventing of the rotation of the scraper element during its longitudinal 7 movement so that the scraper per se will be maintained in contact with the bottom of the boiler at all times.

Still a further object is to provide a boiler ,scale removing device which is simple in construction, inexpensive, strong, and durable and further well adapted to the purposes for which it is designed. j J

Other objects and advantages will become apparent during the course of the following description. i i In the'acompanying drawing, forming a part of this specification, and in which like numerals indicate like parts throughout 4 the same:

Figure 1 is a view partly in section of vice embodying my invention showing the same positioned in marine steam boiler.

Figure 2 is an enlarged sectional view takpartly in elevation and object is to provide a boiler the boiler scraping deen approximately on the line 22 of ure 1, 1 Figure 3 is a sectional view taken on the line 3-3 of Figure 2 looking downwardly and Y r v i i 7 figure at is a detail perspective View of. the scraper carrying arm showing the scrap; er attached to the lower ends'thereof. In the drawings, wherein for the purpose of illustration I have shown a preferred embodiment of my invention, the numeral I designates'the cylindrical shell of a two flue marine steam boiler which is formed in its bottom with the usual sediment discharge opening 2 around which extend the depending mud drum legs or pipes 3 having com munication with the conventional mud drums or settling chamberst in the manner well known in the m; t l The usual fire tubes extend longitudinally through the shellas indicated at 5 in Figure 2 and the water circulates around in the shell in a manner also well "known in the art."

vice includes a tubular casing 6 which is horizontal plane of the fire'tubes and this leasing, is suspended from the top of the shell by means of the hangers 7 as suggested very clearly in Figures 1 and2 of the drawings. 'lhe ends of the casing are open and are internally threaded for receiving the inter nally threaded caps 8 and 9 respectively. A hanger '10 is associated with the rear cap 8 as indicated in Figure 1. Theiorward cap 9 is ,formed with a central opening into which is sleeve 11 and is provided with a flange l2 and engages with the outer side of the forward endof the shell and. extending longitudinally'within the casing. is the feed screw 13, the rear end beingj'ournaled in a suitable8bearing 14 provided therefor. on the. a

,Theforward end of this feed screw which is unthreadedextends through the sleeve 11 and has aii actuating crank 15 secured theref Myimproved' boiler scale. removing. de-

threaded the on for facilitating the turning of the feeding screw although it is to be understood that this feed screw may be driven by an electric motor not shown if so desired.

A stuffing box 16 is associated with the outer end of the sleeve 11 and the unthreaded portion of the feed screw as clearly su gested in Figures 1 and 8. The casing 6 1s formed with a longitudinally extending slot 17 in the bottom thereof which slot extends for substantially the full lengthof the casing and the purpose of this slot will be presently described.

The invention further comprehends the provision of a vertically disposed arm 18 and is formed at its upper end with a horizontally disposed interiorly threaded hub 19 for receiving the feed screw 13, the arm18 being disposed through the slot 17 for slidable movement therein.

The lower end of this arm is formed with a bifurcated head 20 in which is removably secured the segmental scraper unit 21, the

' scraping elements 22 being adapted for engagement with the bottom of the shell 1 at all times.

The operation of my improved scale removing device may be briefiy stated as follows: Starting with the arm 18 and the segmental scraper unit 21 carried thereby positioned at the forward end of the boiler, it will be observed that when the crank 15 is actuated, the feed screw 13 will cause the internally threaded hub 19 to be fed rearwardly in the casing 6 and thus cause the scraper unit to force any scale or sediment that may have collected on the bottom of the water to be separated therefrom and brushed toward one of the outlet openings 2 and when the scrapers 22 pass over this opening 2, the scale and sediment drops through the mud drum or sediment chamber 4 where it is blown out through the mud drum valve not shown.

In this manner, the bottom of the shell of the boiler will at all times be kept free of scale or sediment so that the water will be properly heated. The simplicity of my device enables the same to be readily and easily installed without necessitating any material operations and furthermore will at all times be positive and efiicient in carrying out the purpose for which it is designed.

While I have shown the preferred embodiment of my invention, it is to be understood that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention and the scope of the appended claim.

Having thus described my invention, what I claim as new is:

In combination with a boiler of the fire tube type wherein the bottom thereof has communication with the usual sediment chamber, of a scraping device comprising a casing arranged longitudinally within the boiler above the horizontal plane of the tubes and formed with a slot in the bottom thereof, vertically supporting brackets supporting the casing from the top of the boiler, a feed screw arranged in the casing, an arm having its upper portion disposed through said slot, an internally threaded hub formet on the upper end of the arm for receiving the feed screw, means for actuating the feed screw to effect the movement of the hub along the feed screw in the casing from one end of the boiler to the other, said arm extending downwardly to a point adjacent the boiler bottom, and a scraper unit carried by the lower end of the arm for engagement at all times within the bottom of the boiler to remove the sediment therefrom and discharge the same into the sediment chamber, said scraper unit including a segmental body portion detachably secured on the lower end of the arm, and scraping elements protruding from the arcuate body at the bottom thereof.

In testimony whereof I aflix my signature.

BAYLOR SPRATT. 

